Wolfenstein Cheats

Gadget Freak (20): Purchase all the upgrades for one of your weapons in the single player campaign.
Game Hunter (10): Kill an enemy of every type in a single player campaign.
Gold Digger (30): Collect all the valuables in a single player campaign.
Gun Nut (10): Collect all the weapons in a single player campaign.
Heavy-Handed (30): Kill 200 enemy players with either the Panzerschreck or the Flammenwerfer in multiplayer.
Honorary Geist (20): Spend two hours in the Veil in a single player campaign.
Hospitalized (10): Finish a match on Hospital, spending the majority of your time on the winning team. (1 min minimum)
Johnny-on-the-spot (30): Give 100 Ammo Packs to teammates in multiplayer.
Ley Vacuum (10): Suck up 5 Veil Pools' worth of Veil energy in multiplayer.
Librarian (20): Collect all the Tomes of Power in a single player campaign.
Man About Town (20): Complete all the Downtown missions in a single player campaign.
Master Spy (20): Collect all the Intel in a single player campaign.
Med School (30): Revive a player, supply a Health Pack, and heal someone using Healing Aura in multiplayer.
Mind your Manors (10): Finish a match on Manor, spending the majority of your time on the winning team. (1 min minimum)
Monitor Tan (30): Collect every collectible in a single player campaign.
Nerd Rage (20): Complete the single player campaign on Hard or U"ber difficulty.
Newbie (10): Complete the Train Station mission in a single player campaign.
Pirate Radio (10): Finish a match on Rooftops, spending the majority of your time on the winning team. (1 min minimum)
Quartermaster (30): Give 100 Health Packs to teammates in multiplayer.
Rampage (20): Kill 200 enemies with Empower in a single player campaign.
Route Canal (10): Finish a match on Canals, spending the majority of your time on the winning team. (1 min minimum)
Run-gineer (30): Use Veil Speed for 30 minutes in multiplayer.
Safe Keeping (10): Finish a match on Bank, spending the majority of your time on the winning team. (1 min minimum)
Shock and Awe (10): Finish a match on Tesla, spending the majority of your time on the winning team. (1 min minimum)
Single Quarter (30): Complete the single player campaign with less than three deaths.
Slumming (10): Complete all the Midtown missions in a single player campaign.
Sneaky Pete (30): Kill 100 enemy players with the Satchel Charge in multiplayer.
Super Soldier (30): Complete the single player campaign on U"ber difficulty.
Surgical Striker (30): Kill 200 enemy players using the Veil Strike in multiplayer.
Test Subject (10): Use every Veil ability once in multiplayer.
Time Out (20): Use the Mire power for more than an hour in a single player campaign.
Unholy Lifeline (30): Revive 250 teammates, including 10 revives in a single match in multiplayer.
Veilophile (10): Spend 5 minutes in the Veil in multiplayer.
Warchest (20): Collect more than $30,000 in a single player campaign.

Unlock Cheats
Beat the game on any difficulty (Achievements won't work).

Boss Tips
Here are some tips for beating the final boss:

For the first part, use Empower to get through his shield. Use explosives -- the Panzer Rocket Launcher and the Veil Blue Rocket Launcher.
For the second part you can use either the Slow Motion or Empower once again to beat him.
For the third part, dont run up the ramp. Snipe him with a Sniper Rifle or Rocket Launcher. Go slowly. Once you get to the part where you need to climb up stairs, get a weapon ready to kill large amounts of those things on 4 legs (they call 'em Sniffers). There are 4 waves of them. Afterward, simply shoot him until he falls.
For the fourth part, simply shoot him since at this point he will have no power ups. Use the explosives to end him quickly.